Trolleys and hangers for washdown curtains

ABSTRACT

Example trolleys and hangers for washdown curtains are disclosed herein. An example trolley disclosed herein includes features that simplify manufacturing and promote liquid runoff to avoid bacterial growth. Some example trolleys comprise U-bolts, shoulder screws and acorn nuts. In some examples, a frame of the trolley has a nestable V-shape profile that makes the frame readily blanked and formed from sheet metal with minimal waste. In some examples, an example trolley disclosed herein has a pair of rollers that are horizontally offset to a point from which the curtain hangs so that the weight of the curtain tilts the trolley to promote liquid runoff from the trolley&#39;s frame.

FIELD OF THE DISCLOSURE

This patent generally pertains to washdown curtains typically used forclean rooms and more specifically pertains to curtain trolleys andhangers.

BACKGROUND

In contrast to common residential shower curtains that hang from aseries of sliding rings or curtain hangers, industrial washdown curtainstypically hang from a series of trolleys with rollers that travel alongan overhead track to open and close the curtain. Washdown curtains,trolleys and tracks can have features to facilitate washing down orsanitizing the curtain. Thus, washdown curtains are particularlysuitable for use in the food industry.

The tracks of industrial washdown curtains are often located orpositioned higher than residential shower curtain rods. As a result, aperson has to grasp the washdown curtain several feet below the track toslide it open. This creates an unfavorable angle of pull for sliding thecurtain horizontally because a significant vertical component of thepulling force is downward. The downward force increases frictionalhorizontal drag between the curtain hanger and the track. Consequently,unlike residential shower curtains that employ sliding rings, washdowncurtains often have trolleys with rollers to reduce drag or friction.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of example curtain trolleys supporting a washdowncurtain constructed in accordance with teachings disclosed herein.

FIG. 2 is a front and partial cross-sectional view of an example curtainhanger shown in FIG. 1.

FIG. 2A is a cross-sectional view taken along line 2A-2A of FIG. 2.

FIG. 2B is a cross-sectional view taken along line 2B-2B of FIG. 2.

FIG. 2C is a cross-sectional view taken along line 2C-2C of FIG. 2.

FIG. 3 is a front view similar to FIG. 2, but showing an example trackconstructed in accordance with teachings disclosed herein.

FIG. 4 is a front view similar to FIGS. 2 and 3, but showing an exampleroller constructed in accordance with teachings disclosed herein.

FIG. 5 is a front view similar to FIGS. 2, but showing an example rodconstructed in accordance with teachings disclosed herein.

FIG. 5A is a cross-sectional view taken along line 5A-5A of FIG. 5.

FIG. 5B is a cross-sectional view taken along line 5B-5B of FIG. 5.

FIG. 5C is a cross-sectional view taken along line 5C-5C of FIG. 5.

FIG. 6 is a front view similar to FIGS. 2, but showing another examplerod constructed in accordance with teachings disclosed herein.

FIG. 6A is a cross-sectional view taken along line 6A-6A of FIG. 6.

FIG. 6B is a cross-sectional view taken along line 6B-6B of FIG. 6.

FIG. 6C is a cross-sectional view taken along line 6C-6C of FIG. 6.

FIG. 7 is a front and partial cross-sectional view similar to FIG. 2,but showing another example curtain hanger constructed in accordancewith teachings disclosed herein.

FIG. 7A is a projected view taken along line 7A-7A of FIG. 7.

FIG. 7B is a plan view showing example nested trolley frames prior toforming roller-supporting tabs.

FIG. 8 is a front view similar to FIGS. 2-7, but showing another examplecurtain trolley constructed in accordance with teachings disclosedherein.

FIG. 9 is an end view of FIG. 8.

FIG. 10 is an end view similar to FIG. 8, but showing a curtain hangingfrom the example curtain trolley of FIGS. 8 and 9.

DETAILED DESCRIPTION

In FIGS. 1-10 show example trolleys and hangers for suspending awashdown curtain 10 from various tracks. The term, “trolley” refers toany apparatus or frame with rollers for traveling along a track. Theterm, “hanger” refers to any apparatus or structure (e.g., a buildingstructure or rod) from which a curtain can be suspended. In someexamples, a trolley and a hanger can be combined as a single unit orunitary structure. For example, some example trolleys disclosed hereininclude a feature that serves as a hanger. In some examples, a trolleyand a hanger disclosed herein share some of the same parts, componentsor structure. For example, some example trolleys disclosed hereininclude an axle that supports a roller and also provides a hook forsuspending a curtain therefrom. In examples disclosed herein, horizontalsurfaces (i.e., surfaces parallel to an axis of a track along which thecurtain travels and/or a travel path of the curtain as the curtain ismoved between an open position and a closed position) are avoided orminimized to help prevent the accumulation of moisture, bacteria and/orother particulate that may otherwise form or accumulate on suchhorizontal surfaces.

In the example illustrated in FIGS. 1 and 2, a plurality of curtaintrolleys 12 is shown suspending curtain 10 from an overhead track 14above a floor 16. Examples of track 14 include, but are not limited to,a substantially cylindrical member (e.g., a pipe), a round rod, astructural angle iron (e.g., track 14 a of FIG. 3), other structuralmembers, rectangular bar stock, rectangular tubing, triangular shapedtubing, etc. In some examples, a mounting plate 18 may be employed toprovide additional rigidity to track 14 and enable attachment of track14 to an upper mounting surface 20 such as, for example, to a ceiling.

In some examples, each trolley 12 comprises a frame or rod 22 supportinga pair of rollers 24 to facilitate or provide smooth travel along track14. Rod 22, in some examples, has a curved section 22 a that extendsthrough an aperture 26 in curtain 10 for hanging the curtain. In theillustrated example, rod 22 has a longitudinal centerline 28 curved in aU-shape to provide rod 22 with a first leg 22 b and a second leg 22 c,each extending upward from curved section 22 a. In some examples, rod 22has a substantially round and substantially uniform cross-sectional area30 perpendicular to longitudinal centerline 28 at first leg 22 b, atsecond leg 22 c and at curved section 22 a, as shown in FIGS. 2A, 2B and2C, respectively. In other examples, the cross-sectional areas 30 of thefirst leg 22 b, the second leg 22 c and the curved section 22 a may benon-uniform. For example the cross-sectional area 30 of the legs 22 band 22 c may be smaller than the cross-sectional area 30 of the curvedsection 22 a. The pair of rollers comprises a first roller 24 mounted tofirst leg 22 b such that first roller 24 rotates about a firstrotational axis 32 that is substantially collinear or coaxially alignedwith longitudinal centerline 28 at first leg 22 b. A second roller 24 ismounted to second leg 22 c such that second roller 24 rotates about asecond rotational axis 34 that is substantially collinear or coaxiallyaligned with longitudinal centerline 28 at second leg 22 c.

In some examples, first roller 24 is secured or captured axially in adirection along the first rotational axis 32 between a first stakeddeformation, shoulder or protrusion 36 and a first end cap 38. The firstend cap 38 is removably attached, clamped or otherwise coupled to afirst end 40 of first leg 22 b, and deformation 36 provides a radialprotrusion at an intermediate location on first leg 22 b. Likewise,second roller 24 is secured or captured axially in a direction along thesecond rotational axis 34 between a second staked deformation, shoulderor protrusion 40 and a second end cap 38. The second end cap 38 isattached, clamped or otherwise coupled to a second end 42 of second leg22 c, and deformation 40 provides a radial protrusion at an intermediatelocation on second leg 22 c. In the illustrated example, the end caps 38are threadably coupled to the first and second legs 22 b and 22 c. Eachof the first and second legs 22 b and 22 c have threads 44 to threadablyreceive the end caps 38.

Rollers 24, and other example rollers, can be made of any suitablematerial. Example roller materials include, but are not limited to,nylon, polycarbonate, polyurethane, acetal (e.g., Delrin) and stainlesssteel. To prevent threads 44 on legs 22 b and 22 c from abrading aninner bore 46 of rollers 24 as rollers 24 rotate, in some examples, asleeve 48 (e.g., a bearing) is inserted between threads 44 and bore 46.Sleeve 48 is made of any suitable material. Examples of sleeve materialsinclude, but are not limited to, stainless steel, brass, plastic, etc.To prevent threads 44 from abrading sleeve 48, in some examples, sleeve48 is prevented from rotating relative to the threads 44. In exampleswhere sleeve 48 is prevented from rotating, relative rotation andcircumferential sliding may occur between roller 24 and the generallysmooth outer surface of sleeve 48. To prevent sleeve 48 from rotating orsliding relative to the threads 44, in some examples, end cap 38 is inthe form of a nut that clamps or captures sleeve 48 against deformation40 to prevent axial and rotational movement of the sleeve (48) relativeto the axis of rotation 32 and/or 34. In some examples, a tight radialfit between sleeve 48 and threads 44 holds sleeve relatively fixedrelative to threads 44 to prevent movement (e.g., rotation and/orsliding) of the sleeve 48 relative to the threads 44. In some examples,only a portion of legs 22 b and 22 c above the location of the rollers24 is threaded to receive the cap 38 such that the sleeve 48 can beremoved.

To prevent moisture and bacteria from collecting atop end caps 38, insome examples, end caps 38 have an upper surface 50 that slopes downwardfrom a peak 52 (e.g., a curved or arcuate profile). A conventional acornnut is one example of an end cap having such a peak and downward slopingsurface.

To prevent moisture and bacteria from collecting on rollers 24, in someexamples, rollers 24 have a curved outer surface 54 (e.g., substantiallyspherical) as shown in FIGS. 1-3. Curved outer surface 54 providesroller 24 with a substantially circular rolling line of contact 56 withtrack 14. In other examples, as shown in FIG. 4, a roller 58 hasgenerally conical surfaces or profile 60 for draining moisture and forengaging track 14.

In the example shown in FIG. 1-3, rod 22 is in the form of a standardU-bolt, wherein legs 22 b and 22 c are substantially vertical andparallel. With such a configuration, a plane 62 lying tangent to curvedouter surface 54 and intersecting the circular rolling line of contact56 is tilted out of parallel alignment relative to longitudinalcenterline 28 at first and second legs 22 b and 22 c. As a result, track14 exerts a normal contact force 64 having both vertical and horizontalcomponents. The vertical component urges roller 24 up against theunderside of end cap 38, thus preventing a moisture-collecting gapbetween roller 24 and end cap 38. The horizontal component of force 64helps center rod 22 to track 14, thus preventing rod 22 from dragging,sliding or otherwise scraping along the side of track 14.

FIGS. 5, 5A, 5B and 5C show another example shape or profile of a rod22′, where the drawing figures correspond to similar FIGS. 2, 2A, 2B and2C. In this example, rod 22′ has a relatively V-shaped profile. FIGS. 6,6A, 6B and 6C show yet another example shape or profile of a rod 22″,where the drawing figures correspond to similar FIGS. 2, 2A, 2B and 2C.In the illustrated example, rod 22″ has a first portion that issubstantially straight relative to first and second leg portions, whichare angled relative to the first portion. For example, the rod 22″ has atriangular-shaped profile. The first portion, for example, has alonglongitudinal axis that is substantially perpendicular to a longitudinalaxis of the track 14.

In the example shown in FIGS. 7, 7A and 7B, an example curtain trolley66 includes a pair of rollers 68 mounted to a frame 70 comprising aunitary piece of sheet metal. The term, “unitary piece” refers to frame70 as being one continuous piece of material, as opposed to an assemblyor fabrication of multiples pieces. The term, “sheet metal” refers to apiece having a substantially uniform material thickness, where thethickness is at least three times smaller than the piece's width andlength. Sheet metal is readily blanked and formed using conventionalmanufacturing processes.

In the illustrated example, frame 70 comprises a first leg 70 a and asecond leg 70 b extending upward from a lower section 70 c. A first tab70 d with a hole 72 for mounting first roller 68 extends from first leg70 a and is tilted out of coplanar alignment with first leg 70 a (e.g.,protrudes away from first leg 70 a). A second tab 70 e with hole 72 forsupporting second roller 68 extends from second leg 70 b and is tiltedout of coplanar alignment with second leg 70 b. Tabs 70 d and 70 e areformed by bending a sheet metal blank along lines 74 and 76,respectively. Tabs 70 d and 70 e slope downward toward each other topromote drainage. With tabs 70 d and 70 e sloping downward, a first axle78 and a second axle 80 are tilted out of parallel alignment with eachother. In some examples, axles 78 and 80 are shoulder screws about whichrollers 68 rotate. Some examples of rollers 68 are cylindrical (e.g.,cylinders) and ride upon track 14.

Frame 70 is generally V-shaped such that a concave upward facing edge 70f runs from first leg 70 a, along lower section 70 c and to second leg70 b. A convex downward facing edge 70 g extends from first leg 70 a,along lower section 70 c and to second leg 70 b. Frame 70, being made ofsheet metal, has a geometry that renders convex downward facing edge 70g nestable (e.g., can nest) within a virtual or actual concave upwardfacing edge 70 f of a virtual or actual identical unitary piece of sheetmetal 70′. A nesting arrangement, as shown in FIG. 7B, allows aplurality of sheet metal blanks 82 to be cut from a single larger sheetof material with minimal waste. Some examples of frame 70 have acurtain-receiving notch or hook 84 for hanging curtain 10.

In the example shown in FIGS. 8, 9 and 10, an example curtain trolley 86includes a pair of rollers 88 mounted to a frame 90 comprising a unitarypiece of sheet metal. Each roller 88 is an example of a rollerapparatus, wherein the term, “roller apparatus” refers to one or morerollers rotatable about a single linear axis. Examples of a rollerapparatus include a single roller on one axle, two collinear rollers onthe same axle, and any plurality of collinear rollers sharing the sameaxle. Frame 90 is bent or formed in a V-shape having a first leg 90 aand a second leg 90 b extending upward from a lower section 90 c. Insome examples, first and second legs 90 a and 90 b have, respectively,first and second substantially flat faces 92 a and 92 b that facedownward or away from the track 14. First and second substantially flatfaces 92 a and 92 b define a pair of planes 94 a and 94 b, respectively,that intersect along a line 96 proximate lower section 90 c.

A first axle 98 defining a first axis 100 connects a first roller 88 tofirst leg 90 a, and a second axle 102 defining a second axis 104connects a second roller 88 to second leg 90 b. In some examples, axles98 and 102 are standard shoulder screws. First and second axles 98 and102 are attached to frame 90 and extend upward from first and secondanchor points 105 and 106, respectively. With frame 90 being generallyV-shaped, axles 98 and 102 are tilted out of parallel alignment witheach other.

To promote drainage from frame 90 and thus avoid harboring bacteria,curtain trolley 86 has a curtain hanging point or hook 108 that isoffset relative to (e.g., the axes 100 and 104 of) rollers 88 so thatcurtain trolley 86 hangs from track 14 at an angle 110 while supportingcurtain 10, as shown in FIG. 10. In other words, the trolley 86 hasrollers 88 that are horizontally offset by a dimension 114 relative to apoint 108 from which the curtain 10 hangs so that the weight of thecurtain 10 tilts the curtain trolley 86 to promote liquid runoff fromthe frame 90. Specifically, axes 100 and 104 lie along and define aplane 112, and hanging point 108 is offset and spaced apart from plane112 as indicated by dimension 114 in FIG. 9.

Although certain example methods, apparatus and articles of manufacturehave been described herein, the scope of the coverage of this patent isnot limited thereto. On the contrary, this patent covers all methods,apparatus and articles of manufacture fairly falling within the scope ofthe appended claims either literally or under the doctrine ofequivalents.

1. A curtain trolley comprising: a rod having a longitudinal centerlinethat defines a first leg and a second leg extending upward from a curvedlower section, the rod having a substantially round and substantiallyuniform cross-sectional area perpendicular to the longitudinalcenterline at the first leg, at the second leg and at the curved lowersection; a first roller mounted to the first leg, the first rollerhaving a first rotational axis substantially collinear with thelongitudinal centerline at the first leg; a second roller mounted to thesecond leg, the second roller having a second rotational axissubstantially collinear with the longitudinal centerline at the secondleg; a first cap adjacent the first roller and attached to the firstleg; and a second cap adjacent the second roller and attached to thesecond leg.
 2. The curtain trolley of claim 1, wherein the longitudinalcenterline is curved in a U-shape.
 3. The curtain trolley of claim 1,wherein the first roller and the second roller each have a substantiallyspherical surface and a substantially circular rolling line of contactthereon.
 4. The curtain trolley of claim 1, further comprising a track,wherein the first and second rollers roll upon the track with the curvedlower section hanging beneath the track.
 5. The curtain trolley of claim4, wherein the track is substantially cylindrical.
 6. The curtaintrolley of claim 4, wherein the first roller has a curved outer surfacecontacting the track to define a substantially circular rolling line ofcontact on the curved outer surface such that a plane lying tangent tothe curved outer surface and intersecting the substantially circularrolling line of contact is tilted out of parallel alignment with thelongitudinal centerline at the first leg.
 7. The curtain trolley ofclaim 1, wherein the first leg is substantially parallel to the secondleg.
 8. The curtain trolley of claim 1, further comprising a firstsleeve on the first leg with the first roller being rotatable relativeto the first sleeve.
 9. The curtain trolley of claim 1, wherein thefirst cap has an upper surface sloping downward from a peak of the uppersurface.
 10. The curtain trolley of claim 9, wherein the first cap is adomed acorn nut.
 11. The curtain trolley of claim 1, further comprisinga deformation providing a radial protrusion on the first leg, whereinthe first roller is captured between the first cap and the radialprotrusion.
 12. The curtain trolley of claim 1, further comprising acurtain defining an aperture therethrough, wherein the curved lowersection of the rod passes through the aperture and the curtain hangsfrom the curved lower section. 13.-29. (canceled)
 30. A curtain trolleycomprising: a unitary rod having a first leg and a second leg extendingupward from a lower section, the first leg defining a first axle and thesecond leg defining a second axle, the lower section to extend throughan aperture in a curtain to hang a curtain; a first roller mounted tothe first axle; and a second roller mounted to the second axle.
 31. Thecurtain trolley of claim 30, wherein the rod has a longitudinalcenterline that is curved in U-shaped profile to provide the first legand the second leg.
 32. The curtain trolley of claim 30, whereincross-sectional areas of the first leg, the second leg and the lowersection are substantially uniform.
 33. The curtain trolley of claim 30,wherein the first roller to rotate about a first rotational axis definedby the first axle and the second roller to rotate about a secondrotational axis defined by the second axle.
 34. The curtain trolley ofclaim 33, wherein first roller is captured axially in a direction alongthe first rotational axis and the second roller is captured axially in adirection along the second rotational axis.
 35. The curtain trolley ofclaim 34, wherein the first roller is captured between a first shoulderdefined by the first leg and a first cap coupled to a first end of thefirst leg.
 36. The curtain trolley of claim 35, wherein the secondroller is captured between a second shoulder defined by the second legand a second cap coupled to a second end of the second leg.
 37. Thecurtain trolley of claim 36, further comprising a first sleeve providedbetween a first inner bore of the first roller and a first outer surfaceof the first leg and a second sleeve provided between a second innerbore of the second roller and a second outer surface of the second leg.38. The curtain trolley of claim 37, wherein the first sleeve is clampedbetween the first cap and the first shoulder of the first leg to preventthe first sleeve from rotating about the first rotational axis, and thesecond sleeve is clamped between the second cap and the second shoulderof the second leg to prevent the second sleeve from rotating about thesecond rotational axis.
 39. The curtain trolley of claim 36, whereineach of the first and second caps have spherical profiles to preventmoisture or bacteria from collecting atop of the respective first andsecond caps.
 40. The curtain trolley of claim 30, wherein the rod has aU-shaped profile.
 41. The curtain trolley of claim 30, wherein the rodhas a V-shaped profile.
 42. The curtain trolley of claim 30, wherein therod has a triangular-shaped profile.
 43. A curtain trolley comprising: aframe; a first leg protruding from a first portion of the frame todefine a first rotational axis, at least a portion of the first leghaving a first threaded portion; a second leg protruding from a secondportion of the frame to define a second axis, at least a portion of thesecond leg having a second threaded portion; a first roller apparatusmounted to the first leg to rotate about the first axis; and a secondroller apparatus mounted to the second leg to rotate about the secondaxis.
 44. The curtain trolley of claim 43, wherein the frame includes afirst shoulder formed adjacent the threaded portion of the first leg anda second shoulder formed adjacent the threaded portion of the secondleg.
 45. The curtain trolley of claim 43, further comprising a first capto be threaded to the threaded portion of the first leg to couple thefirst roller to the first leg and a second cap to be threaded to thethreaded portion of the second leg to couple the second roller to thesecond leg.
 46. The curtain trolley of claim 43, further comprising afirst sleeve positioned between a first inner bore of the first rollerand the threaded portion of the first leg and a second sleeve positionedbetween a second inner bore of the second roller and the threadedportion of the second leg.